An actuator that generates electrochemical extension/contraction or warping is provided with a pair of electrodes and, by applying a voltage to the respective electrodes, migration of electric charge or the like occurs, whereby driving of extension/contraction or warping can be carried out (See, for example, Patent Document 1)).
For example, suppose that one of the aforementioned pair of electrodes is allowed to be an extensible and contractible working electrode containing an electroconductive polymer as a principal material, and the other one is allowed to be an opposing electrode made of a platinum electrode. When a positive electric potential is applied to the aforementioned working electrode, the electroconductive polymer captures anions and the aforementioned working electrode extends, and when a reverse electric potential is applied to the aforementioned working electrode, the aforementioned working electrode contracts, whereby the aforementioned actuator undergoes extension/contraction driving.    Patent Document: Japanese Patent Application Laid-Open (JP-A) No. 2004-162035